Motivated by previous studies of QSO spectra that reported a variation of the fine structure constant alpha, a search for C IV and Si IV doublets was conducted in the absorption spectrum toward QSO 1101-264, obtained by VLT-UVES during the Science Verification. Seven C IV and two Si IV systems were identified and accurate measurements of wavelengths over the redshift range 1.1862 < z < 1.8377 were performed. After a careful selection of pairs of lines, the Alkali Doublet method with a derived analitical expression for the error analysis was applied to compute the alpha variation. The result according in magnitud order with previous doublets measurements, corresponds to one Si IV system: Delta alpha/alpha = (- 3.09 +/- 8.46) x 10^(-5).
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